SRU - frequently asked questions (FAQ) / Troubleshooting
What is the difference between SRU and OAI?
SRU permits users to conduct a specific search without the need for a database of their own.
OAI permits continuous synchronisation of large amounts of data; this is based on the import of data from an up-to-date basic stock to a separate database.
Where do I find software and tools for SRU?
The webpage of the Library of Congress provide a list of software and tools for SRU.
What happens if a parameter in the URL request is incorrect or not supported?
The SRU interface returns an error diagnosis in XML (diagnostic) format as stipulated by the standard.
What happens if no index is given in a request?
If no index is given, the query is sent to the largest index of the selected catalogue (fallback).
What happens with diacritical marks, spaces or the slash mark?
These must be converted in an SRU request into URL code (UTF-8 hexadecimal, also known as percent encoding). For example, the letter ä is converted to %C3%A4, a space to %20 and a slash to %2F. Search keys can be enclosed in quotation marks ("search key"). If a search key contains the characters < > = / ( ) or space, these must be enclosed in quotation marks (e.g. "1w/r" in URL coding = "1w%2Fr" - see standard).
How is markup transported in a SRU response?
Markup is transported in a CDATA section.
What happens in the event of a request for which no matching data exists?
The SRU interface returns "number of records 0".
What happens in the event of a requests concerning an unauthorised IP address?
The SRU interface returns "Not authorized to send record in this schema / MARC21-xml. No Account for IpAddress: XXX.XXX.XXX.XXX ".
How do I obtain an access token and how do I formulate an access token request?
Once you are logged in and authorised, you will be able to access the "Interfaces Access management" menu item under "My Account / Access data". There you can generate and manage the access token.
- There are two accepted possibilities for incorporating the access token:
Entry in the base URL with ~ (tilde) separator (~)
Parameter / value within the request
Last update: 02.02.2016